Reheat furnaces are used to heat heavy slabs of metal (work pieces) which are moved through the furnace supported on water cooled structural members called skid rails. These skid rails include a wear bar secured to the top of the skid rails for contact with the slabs. The contact between the wear bars and the slabs allows heat transfer from the slabs to the skid rails which produce lines of chilling sometimes called "tiger stripes". Elimination of such tiger stripes is desired particularly where the slabs are to be used in producing steel strips so that a uniform gauge strip may be produced.
An example of the work of the prior art to eliminate these tiger stripes is shown in U.S. Pat. No. 4,354,824 wherein the wear bars secured to the top of the structured member are staggered, spaced apart and the top surface of the structural member covered between the wear bars with a metal honeycomb reinforced insulation. While such structure has been very successful in minimizing the heat transfer from the slab to the skid rail, the wear bars still allow some cooling of the slab.
Another example of the prior art is disclosed in U.S. Pat. No. 3,214,152 which discloses a work engaging means supported from a rail on two stacked blocks made of ceramic material with the lower block which engages the structural member having a density substantially less than the upper block. It also suggests that the work engaging means may be made of a material having a very high resistance to heat such as cobalt or molybdenum. The use of low density ceramics as a support may provide heat insulation but is subject to damage when heavy work pieces are moved over the work engaging means.